Braking system for assisting in steering



May 6, 1941.

' A. N. MILSTER 2,241,214

FIG.\.

INVENTOR MILSTER ATTORNEY l 3 I BY May 6, 1941. A. N. MILSTER BRAKINGSYSTEM FOR ASSISTING IN STEERING 2 Sheets-Sheet 2 Filed Feb. 15, 1940 EMT s NL WM u W ATTORNEY Patented May 6, 1941 UNITED STATES PATENTOFF-ICE BRAKING SYSTEM FOR ASSISTING IN STEERING Arthur N. Milster,Ferguson, Mo., assignor to Wagner Electric Corporation, St. Louis, Mo.,a

corporation of Delaware Application February 15, 1940, Serial No.318,981

11 Claims.

My invention relates to a fluid pressure actu-,

system which will permit two brakes to be applied either simultaneouslyor individually by a single pressure producing device.

Still another object is to produce an improved l cylinder incommunication with the fluid motor brake actuating system for the brakesof two of the right-hand brake assembly have interposed wheels of avehicle which can be socontrolled th-erebetween a shut-oil valve 26 andalso interby the operator that the brakes can be employed posed betweenthe conduits i3 and I4 leading to toassist in steering. I the fluidmotor of the left-hand brake is another Other objects of my inventionwill become apl5 shut-off valve 21., Both of these valves are of parentfrom the following description taken in like construction and as shownin Figure 2 each connection with the accompanying drawings in comprisesa casing 28 provided with chambers 29 which Figure 1 is a view of afluid pressure acand 30 connected together by a passage 3|. A tuatedbraking system embodying my invention; valve seat 32 is associated withpassage 3| and Figure 2 is an enlarged sectional view of one ofcooperating with this seat is a valve 33 mounted the control valves;Figure 3 is a side view showon a valve stem 34. .A spring 35 normallybiases ing the control connections between the cross the valve towardseated position. The stem of shaft and the master cylinder and betweenthe the valve extends through passage 3| and is iiutbrake pedal and themaster cylinder; and Figure ed to permit passage of fluid. Within thecham- 4 is a side view showing the connections between her of the valvecasing is a cross shaft 36 carone of the hand levers, the cross shaftand the rying a cam 31 for engaging the end of the stem associatedcontrol valve. to move the valve element off its seat. This shaftReferring to the drawings in detail and paralso carries a shoulder 38for engaging the side ticul-arly Figure 1, there is shown a right-handof the stem to limit the rotation of the shaft in braking assembly I forbraking a wheel 2 and a 30 one direction. The outer end of the shaft carleft-hand braking assembly 3 for brakingawheel ries an arm 39 forrotating it to control the 4. Each of these braking assemblies comprisesvlave 33. The chamber 29 of the valve 26 is pivoted shoes 5 and 6mounted on a backing, connected to conduit ll coming from the masterplate 1 and adapted to be actuated into engagecylinder and the chamber30 of the valve is conment with a drum 3 by means of a fluid motornected to conduit Ill leading to the fluid motor of 9. Thefluid motor ofthe right-hand brake is the right-hand brake assembly I. Similarly theconnected by conduits l9 and II to a master cylchamber 29 of valve 21 isconnected to conduit inder device l2 and the fluid motor of the left- I4coming fro the master Cylinder a c a be hand brake is connected to thissame master 30 is connected to conduit l3'leading to the fluid cylinderby conduits l3 and I4. 9 motor of the left-hand brake assembly 3.

The master cylinder device, as best shown in As shown in detail inFigure 4, the valve 26 is Figure 3, is of the usual construction andcomadapted to be controlled by a hand lever 40 which prises a cylinderl5 in which is reciprocable a has its lower arm 41 connected to one endof a pressure producing piston IS. A sealing cup I1 rod 42. The otherend of this rod is operatively is associated with the head of the pistonand connected to the arm 39 of the valve through a when the piston andcup are in their normally spring 43, said spring being interposedbetween retracted position they uncover a porthole 18 for the adjustablenuts 44 on the end of the rod placing the cylinder and the brakingsystem in and a sleeve 45 receiving the rod and pivoted to communicationwith a reservoir l9 to thus perthe end of arm 39. The rod 42 also hasfixed mit contraction and expansion of the fluid. The thereon a collar46 which is adapted to engage piston of the master cylinder is adaptedto be a sleeve 41 slidable on the rod and pivotally conactuated by apiston rod 20 and a brake pedal nected to an arm 48 carried by a crossshaft 2|, the latter being held in its normally inoper- 49. The collar46 is so positioned on the rod ative position by a spring 22. Theconnection that it will be spaced from the sleeve 41 when between thepedal and the piston rod is such as to permit the piston rod'to be movedto actuate the piston independently of the brake pedal and as showncomprises a collar 23 fixed to the piston rod and capable of beingabutted by the end 24 of the pedal extending below the pivot 25. Thepiston rod extends through an enlarged hole in the end of the pedal andto a point beyond for a purpose to be later referred to.

The conduits Ill and II which place the master I the lever 41 is in itsinoperative position but will abut sleeve and hold valve 33 open. Aspring it maintains the lever in its inoperative position.

\ The shut-off valve 21 is adapted to be controlled by a second lever 5|which has its lower arm 52 connected to arm 39 of the valve 21 by thesame structure previously described with respect to the connectionbetween lever 40 and the same manner as that described with respect 7 toarm 48 on the other end of the cross shaft.

The lever BI is held in inoperative position by a spring 54 which alsoholds the valve 2! open.

The cross shaft 49 is so positioned that it extends beneath the extendedend of the piston rod which a previously described actuates the pistonof the master cylinder device. In order that this piston rod may beactuated by the cross shaft there is secured to the latter an arm .55capable of abutting a collar 56 on the end of the piston rod, whichextend through an enlarged opening in the end oithc arm.

In operation both valves 28 and 21 are normally held open by the actionof the springs 50 and 54 on the levers thus permitting fluid to flow inboth directions through the valve. If it is desired to apply both brakessimultaneously the brake pedal can be operated and fluid under pressurewill be simultaneously transmitted to both the fluid motors 9 of the twobraking assemblies. Actuation of the piston rod by the pedal will notcause any movement of the cross shaft.

If it is desired to apply the right-hand brake only to assist insteering the vehicle lever 5| is pulled rearwardly. This will firstcause valve 21 to be closed and then the collar 46 engaged with arm 53on the cross shaft. Continued movement of the lever 5| rearward willthen cause the arm 55 on the cross shaft to move .the piston rod 20 andoperate the master cylinder to develop fluid under pressure withoutoperation of the brake pedal. Since the valve 21 is closed, fluid underpressure cannot be transmitted to the fluid motor of the left-hand brakebut fluid under pressure can be transmitted to the fluid motor of theright-hand brake since the valve 26 remains open due to the sliding ofsleeve 41 on the rod 42 as the arm 48 is moved with the cross shaft. Itis thus seen that the right-hand wheel will be braked and held frommovement and the lefthand wheel will remain free to rotate. Thus, if thesteering wheel or wheels of the vehicle (not shown) have been turned toa position to steer the vehicle to the right a very short turn will bemade since the vehicle will now turn around the braked wheel 2 as anaxis.

If it is desired to turn the vehicle short to the left by braking theleft-hand wheel, the left.- hand lever is grasped and pulled rearwardly.This will first cause valve 26 to be closed to prevent fluid pressurefrom being transmitted to the fluid motor of the right-hand brake andthen the master cylinder device operated to apply the lefthandbrake.Thus the left-hand wheel 4 will be braked and the right wheel permittedto rotate freely so the vehicle can be steered around the wheel 4 as aturning axis.

In mounting the braking system on the vehicle, the lever 40 is mountedwithin easy reach of the left hand of the operator and lever 5| ismounted within easy reach of the right-hand of the operator. Since theleft-hand lever is employed to assist in steering to the left and theright-hand lever employed to assist in steering to the right, there willbe no possibility of confusion in operating theselevers.

By the use of the braking system described to .assist in steering, ahand lever only needs to be operated thus leaving the foot free to beemployed for other purposes. The only time that the brake pedal isemployed is when it is desired to operate the two brakes simultaneously.The

braking system is very well adapted for use on limited except as setforth by the appended claims.

Having fully described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. In braking mechanism, two brakes, means for actuating both brakessimultaneously, means for disconnecting one brake so that it cannot beactuated by said first named means, and means controlled by theoperation of a single member for successively operating the second namedmeans and the first named means.

2. In a fluid pressure braking mechanism, two brakes, fluid pressureactuated means for applying the brakes simultaneously, and meanscontrolled by a movement of a single control member for first soconditioning the-fluid pressure actuated means that fluid pressurecannot be transmitted to actuate one of said brakes and then by anadditional movement of said control member to cause subsequent operationof the fluid pressure actuated means to apply the other brake.

3. In a fluid pressure braking mechanism, two brakes each including anactuating fluid motor, a pressure producing means, conduit means forconnecting the fluid motor of one brake to the pressure producing means,conduit means for connecting the fluid motor of the other brake to thepressure producing means, a shut-01f valve for each conduit means, meansfor closing each shut-off valve independently of the other and means foroperating the pressure producing means by either last named means afterit has closed the shut-off valve it operates.

4. In afluid pressure braking mechanism, two brakes each including anactuating fluid motor, a pressure producing means, conduit means forconnecting the fluid motor of one brake to the pressure producing means,conduit means for sure producing device, conduit means for connectingthe fluid motor of the other brake to the pressure producing device, ashut-off valve for each conduit means, and means for closing eithershut-off valve independently of the other and subsequently operating thepressure producing device without manual operation of the manual member.

6. In a fluid pressure braking mechanism, two brakes each including anactuating fluid motor, a pressure producing device, conduit means forconnecting the fluid motor of one brake to the pressure producingdevice, conduit means. for connecting the fluid motor of the other braketo the pressure producing device, a shut-off valve for each conduitmeans, a hand lever connected to close each valve, and an operativeconnection between each lever and the pressure producing device foractuating the latter after said lever has closed the valve with which itis connected.

7. In a fluid pressure braking mechanism, two brakes each including anactuating fluid motor,

a pressure producing device, a brake pedal foroperating the device,conduit means for connecting the fluid motor. of one brake to thepressure producing device, conduit means for connecting the fluid motorof the other brake to the pressure producing device, a shut-off valvefor each conduit means, a hand lever connected to close each valve, andan operative connection between each lever and the pressure producingdevicei'or actuating the latter without manual operation of the pedaland after. said lever has closed the valve with which it is connected.

8. In a fluid pressure braking mechanism, two brakes each including anactuating fluid motor, a master cylinder device, a brake pedal foroperating the master cylinder, conduit means for connecting the fluidmotor of one brake to the master cylinder, conduit means for connectingthe fluid motor of the other brake to the master cylinder, a shut-oi!valve for each conduit means, a shaft operatively connected to actuatethe master cylinderindependently ofthe pedal, a hand lever associatedwith each valve, and connecting means between each hand lever, itsassociated valve and the shaft for causing said valve to be closed andthen the shaft to be subsequently 'master cylinder independently of thepedal, a

hand lever associated with each valve, and an operative connectionbetween each hand lever, its associated valve and the shaft, saidconnection comprising a lost motion permitting closing of the valve byits lever prior to rotation of the shaft, said connections alsoembodying meanspermitting one lever to rotate the shaft withoutmovementof the other lever.

10. In fluid pressure actuating mechanism, two fluidmotors amanually-controlled source of pressure, conduit means for connecting thesource to the two fluid motors, two valves associated with the conduitmeans and each preventing fluid pressure from the source from actuatinga fluid motor, manually-controlled independently operated means forclosing each valve, and means operated by either last named means forcausing said source of pressure to apply fluid pressure to the fluidmotor connected thereto after the associated valve is closed to preventthe fluid motor it controls from being operated.

11. In fluid pressure actuating mechanism, two fluid motors, amanually-controlled source of pressure, conduit means for connecting thesource to the two fluid motors, two valves associated with the conduitmeans and each preventing fluid pressure from the source from actuatinga fluid motor, a lever for closing one valve, a second lever for closingthe other valve, and means for connecting each lever to control thesource of pressure after said lever closes its associated valve. 1

ARTHUR N. MILS'IER.

